I am thinking about trying filters on digital, and am trying to come up with a good starter system.

GND filters: I would like to try shooting sunsets and sunrises with graduated neutral density filters on wide to ultra-wide lenses. I'd like some opinions. Do you personally use GND filters (without or with subsequent post-processing), or do you rely solely on post-processing? Do you ever use the "reverse ND filter" technique of stacking two filters in opposite orientations with overlap? Do you use hard only, soft only, or both types of GND filters? What is your most commonly used strength, one, two, or three stops?

High strength ND filters (6 to 12 stops) For simplifying water or blurring waterfalls, how many stops of ND filter do you find most useful? I see 6, 8, 9, 10, and variable 9 to 12 stop filters for sale, for varying prices. Do you bother with coated or multicoated versions? If you had just one ND filter for long exposure, what stop strength would you pick?

Here are some suggestions on ND use. You are using a 6D, so I would start with a base iso of 50 or 100. With this, you should be able to get to 1 sec in normal outdoor light with a 0.9 (3 stop ND filter) combined with a CL-PL. I recommend the CL-PL around water to cut the glare. It makes a big difference. Most CL-PL filters are between 1 and 2 stops when polarized so with a 0.9 ND you will have around 5 stops. I like to shoot water (for the blur effect) between 1/8th of a sec and 5 to 10 seconds. If it's early or late in the afternoon I might push to 20 seconds. The 16x and 32x ND's from Hoya will get you much longer times but for the effect of water blur in normal streams, they are a bit too much. They are great on ocean shots or sky (cloud blur). Lee also has a filter called the big stopper which works in much the same manner.

You mentioned having a Samyang 14mm and the Zeiss 21mm. The Samyang will not really work with any filter solution I know off, even Lee setup. Lee makes a great solution for the Nikon 14-24 but I don't think it will work on the Samyang. You can't really hold a large sheet filter in front of the Samyang as the tulip sun shade will let in light on the cutouts. Lee makes a 100mm step down adapter, meant to work on a 95mm outer diameter. I am not sure what the outer diameter of the Samyang sun shade is but if it's close to 95mm you might get this to work. You also may be able to adapter a Cokin pro holder or High tech.

The Zeiss will be a lot easier, you can pick from either a few 82mm ND's or get the Lee holder (foundation kit and 82mm wide angle adapter ring). This will let you use (2) 4 x 4 Lee filters. Lee makes two glass 4 x 4 ND's 0.6 and 0.9 both are excellent filters, but a bit on the expensive side. They also make a 4 x 4 square CL-PL that will fit the holder. As long as you use a solid ND Lee or other brand you can use the CL-PL by Lee. A grad will be messed up when you rotate the CL-PL. You can also pick the Lee Wide Angle Hoood, with 1 slot or 2 slots and it will work the same as the foundation kit, but also has the hood. This is what I use on the 18mm Zeiss. One note, if you pick a Lee solution you will need a wide angle adapter ring. You can't use this ring with a normal 82mm CL-PL mounted first, the rotation feature of the CL-PL will make it so you can't get the filter off. The Lee ring fits over the outside to help cut down on vignetting issues.

After carrying a bunch of different ND's and CL-PL's with step up/down rings for years, I have moved to Lee for most of my ND/CL-PL solution. The ND's that are glass are excellent and I can't see any difference in image quality in the Lee vs. a Hoya or Tiffen. Lee claims a bit of IR blocking, but I am not too sure on that. The longer you go, the more IR pollution will possibly effect the outcome. Tiffen makes a great line of IR-ND's but again they get expensive.

Grad ND's are a different issue. They work well on sunrise and sunsets, but if you have any foreground object, trees, rocks etc. that are in the area of the ND, they will be adversely darkened and it will look a bit un-natural. Grad ND's work great on open horizon lines. You can also consider the reverse grads by Singh-ray. Darker near the center and lighter to the top, and on a sundown, sunrise they put the darker area near the center where most likely the horizon will be. For most sunset, sunrise work, I would instead consider exposure bracketing. The 6D will allow you up to 5 brackets and as much as +2, -2 per bracket (I may have this wrong). Excellent solution and there are many great software products to assist in the creation of the image. Nik HDR 2.0 is a great tool for this as it allows for very nice blends without the hard edged 3D look.

If you are in the U.S. I would start at www.2filter.com, ask for Andrea. Great company, and they carry a wide range of brands. They also have IMO the best connection with Lee in the U.S.

I use grads all the time, only reverting to exposure blending if a situation with a lot of inclusions into the top of the frame, trees etc.

I much prefer hard edged grads to soft as there is a danger of blowing the lower part of your sky with a soft edge as they are only the full strength at the top of the filter. With a hard edge you can always dodge back bits darkened unnecessarily in post.

I use all Lee filters (soft and hard grads, 105mm CPL, Big Stopper etc) apart from a Hitech 3 stop reverse grad which is very useful for sunsets and sunrises but does suffer from flare when shooting at an angle to the sun.

I've written a couple of articles introducing grads and long exposures for landscape photography, I don't know what protocol is here for linking to them? I don't want to tread on any toes.

Mark, I think it would be fine to link the article. I did find your blog, and am starting to read a 3/9/13 entry about ND filters. Thanks very much.

One thing about Lee filters is that U.S. orders are fulfilled s-l-o-w-l-y, according to many users. That, plus the price, has made me open to consider other quality filters as well. I take it that the Hitech and Lee filters fit each others' 4" / 100mm holders. Do Lee filters handle flare better than Hitech filters?

I have not used grauated NDs since I went digital. I use the graduated filter in LR4 and it works great for me,Sometimes I use HDR, merge to HDR to in Photoshop, save as a 32 bit image and process with LR standard tools.

If you don't use LR, ACR in Photoshop has the same options.

The way I mostly use graduated filter is to use say a small negative exposure adjustment, say -0.3 and a lot of highlight compression 50-100%. Worth a try?

I use the Lee system when I need to use filters. I find I rarely use the grad nd's any more and find with exposure bracketing and luminosity masking I get better images. The variable ND filters that I have used have not been good, they have color casts and at least the ones I tested were not as dense as they claimed. I have a use for ND filters and I use the Lee and the Hitech, I have done some images with clouds etc. and used a 10 and 6 stop combined or sometimes with other filters to bump up the time. The Filter Connection (2filter.com) is great to deal with and I second the recommendation for Andrea, she is very helpful. Hitech has some good filters that are easier to get than Lee filters and they also have reverse ND grads if you want to get them. I find the Singh-Rays to be way over priced and there are certainly as good filters available for a reasonable amount of money.

I have used a variable ND filter and just didn't like the results and it wasn't a cheap one either. The variable wasn't consistant across the frame and sharpness seemed to suffer a lot more than the fixed filter. I used a 9 stop filter for some time and it was quite good then got a B&W 10 stop filter and that has turned into my favorite. Got them in 77mm to fit my biggest lenses then use step down rings for the other lenses. Variable sounds good but unless someone would money back guarantee it for sharpness and even exposure across the frame I wouldn't touch it. Just my opinion.

I use HiTech and have never experienced a magenta cast with them. This is the first time I've seen anyone mention a colour cast with them. Cokin, on the other hand is one with which I have experienced colour casts and I'm not alone in that.

As was mentioned, grad ND filters can be of limited use depending on what you're shooting. If the horizon isn't straight, or fairly so, grads are less useful.

The 'reversing' technique you refer to isn't one I'm familiar with but there are reverse grad ND filters available that are denser in the middle and fade to the edge. These can be useful in situations, for example, where you have bright areas on water from the sun but the sky in the direction you're shooting is darker.

Variable ND filters are actually two polarisers stacked together. These can be useful and have become popular with DSLR video shooters for adjusting exposure during a shot in response to changing light. They can, and often do, impart colour casts because many people are using cheaply made ones. The other problem with them is at the extreme of the density range, you can get an 'X' effect in the image resulting from the way the light is cross polarised. Versions that don't use good glass (and even some that do) can cause a loss of sharpness as well. The new Eclipse Fader ND from Genus has received quite good write-ups and is reasonably priced.

Thanks, all. I am starting to learn what the Lightroom graduated filter does and how far it can be pushed. I definitely want to try the ND 3.0/ "big stopper" filter. I have already amassed step up rings for all but the newest used lens, which takes 82mm filters. I am debating whether to give the grads a trial. If not, plain 82mm circular ND filter would fill the bill for long-exposure / wide aperture shooting.

Variable ND filters seem to be a good deal for the videographer, perhaps less so for my stills purpose.

I have heard of some cases where ND 3.0 gave a lot of color shifts, it is said to be depending on the density not extending in the IR range. You need to find out how the filter works with your camera. Shooting a grey card is probably a good idea, so you have a good starting point for white balance.

Don't forget to use shutter on viewfinder eyepiece or shading it. Light leaking in through eyepiece can fool the exposure meter.

Thanks, all. I am starting to learn what the Lightroom graduated filter does and how far it can be pushed. I definitely want to try the ND 3.0/ "big stopper" filter. I have already amassed step up rings for all but the newest used lens, which takes 82mm filters. I am debating whether to give the grads a trial. If not, plain 82mm circular ND filter would fill the bill for long-exposure / wide aperture shooting.

Variable ND filters seem to be a good deal for the videographer, perhaps less so for my stills purpose.

I have a couple of Singh Ray GND filters, very high quality. One is 2 stops hard grad, the other is 2 stops soft grad, this gives me a lot of flexibility. I use them quite often, as I shoot a lot of seascapes, where the movement of the waves/sea impairs the option of shooting multiple exposures for later blending.

For subjects that are not moving, as more traditional landscapes, I sometimes use the graduated filter option in LR, which is very nice.

I have not used grauated NDs since I went digital. I use the graduated filter in LR4 and it works great for me,Sometimes I use HDR, merge to HDR to in Photoshop, save as a 32 bit image and process with LR standard tools.

If you don't use LR, ACR in Photoshop has the same options.

The way I mostly use graduated filter is to use say a small negative exposure adjustment, say -0.3 and a lot of highlight compression 50-100%. Worth a try?

Best regardsErik

If the filter induces a colour cast, that should be able to he corrected with a custom white balance. I've experimented with using a piece of welding glass as a ~10 stop ND filter and have been able to correct for the heavy green cast with a custom WB.

If the filter induces a colour cast, that should be able to he corrected with a custom white balance.

Hi Bob,

That of course depends on the type of spectral absorption of the filter. Some filters do not have an absorption that translates to a simple color temperature + tint shift. That doesn't mean it's impossible, but it won't be simple either. Things get increasingly difficult if the filter is transparent for Near-InfraRed, because that will affect all color channels since the Bayer CFA is transparent for IR.

That of course depends on the type of spectral absorption of the filter. Some filters do not have an absorption that translates to a simple color temperature + tint shift. That doesn't mean it's impossible, but it won't be simple either. Things get increasingly difficult if the filter is transparent for Near-InfraRed, because that will affect all color channels since the Bayer CFA is transparent for IR.